This invention relates to a car body comprised of extruded stocks, especially to a side body preferable for a rolling stock of a railway car.
Heretofore, the rolling stock of a railway car, especially the side body thereof, is strongly requested to reduce mass as well as to enhance strength. In order to achieve this contradicting problem, the corner portion of the openings such as windows and the like provided to the side body must be examined from the viewpoint of strength, and various strength enhancement methods have been proposed.
In a side body with a flat plate fixed to the outer surface of the skeleton member, the stress at the corner portion is reduced by adding a thick plate to the corner portion of the openings such as windows and the like provided to the side body, or by enlarging the radius of the circular arc at the corner portion thereof.
In a side body constituted from arranging the extruded stocks in the longitudinal direction of the car body, the plate thickness of the face plates of the extruded stocks at the window region is thickened. The face plates of the extruded stocks from the upper portion of the window to the lower portion of the window is thickened. Moreover, as another embodiment, only the plate thickness of the region corresponding to window corner portion is thickened, and the plate thickness of the central portion is thinned, aiming at weight reduction (Japanese Patent Publication No. H6-45341).
A side body using hollow shape extruded stocks constituted from two face plates and ribs (Japanese Patent Laid-Open No. 2-246863) is designed under the idea similar to that mentioned above. Moreover, enhancement in strength is planned from the plate thickness of the face plates and the pitch of the ribs.
There are cases where plates are welded to the end portions of hollow shape extruded stocks constituting the region between the windows. The plates are positioned between the face plate of the hollow shape extruded stock at the inner side of the car and the face plate at the outer side of the car (Japanese Patent Laid-Open No. H7-257371).
With the prior art, enhancement in strength in the side body using the hollow shape stocks is planned from enlarging the radius at the corner portion, and from the plate thickness of the face plate and the pitch of the ribs. However, the prior art is insufficient in advancing weight reduction and strength enhancement further simultaneously.
The object of the present invention is to provide a car body achieving weight reduction and strength improvement.
In order to solve the above-mentioned object, the first method of the present invention includes;
plate thickness of face plates of the extruded stock at regions in the upper and lower area based on the connection points between the vertical sides of the window and the circular arcs of the corner portion of the window, respectively, being thicker than the plate thickness of face plates of the extruded stocks at upper and lower locations from the regions; and
plate thickness of the face plates between the region having thicker plate thickness based on the connection point at upper portion of the window, and the region having thicker plate thickness based on the connection point at lower portion of the window, being thinner than plate thickness of the region having thicker plate thickness.
As the second method, the present invention arranges a buckling preventive tool in the space surrounded by the face plate and the ribs, to the hollow shape stock constituting the neighborhood of the corner portion of the opening. This technique could be applied to openings other than windows.
As the third method, the present invention thickens the thickness of the face plate at the inner side of the car of the hollow shape stock constituting the side body more than the thickness of the face plate at the outer side of the car.